Metallurgy separation

The essential operations of an extractive metallurgy flow sheet are the decomposition of a metallic compound to yield the metal followed by the physical separation of the reduced metal from the residue. This is usually achieved by a simple reduction or by controlled oxidation of the nonmetal and simultaneous reduction of the metal. This may be accompHshed by the matte smelting and converting processes. 

The preparation, reduction, and refining operations are very much interdependent, and for a given metal must be considered as parts of a single flow sheet. To illustrate the principles of extractive metallurgy, however, it is convenient to discuss the various operations separately. 

The treatments used to recover nickel from its sulfide and lateritic ores differ considerably because of the differing physical characteristics of the two ore types. The sulfide ores, in which the nickel, iron, and copper occur in a physical mixture as distinct minerals, are amenable to initial concentration by mechanical methods, eg, flotation (qv) and magnetic separation (see SEPARATION,MAGNETIC). The lateritic ores are not susceptible to these physical processes of beneficiation, and chemical means must be used to extract the nickel. The nickel concentration processes that have been developed are not as effective for the lateritic ores as for the sulfide ores (see also Metallurgy, extractive Minerals recovery and processing). 

Eigure 3 is a flow diagram which gives an example of the commercial practice of the Dynamit Nobel process (73). -Xylene, air, and catalyst are fed continuously to the oxidation reactor where they are joined with recycle methyl -toluate. Typically, the catalyst is a cobalt salt, but cobalt and manganese are also used in combination. Titanium or other expensive metallurgy is not required because bromine and acetic acid are not used. The oxidation reactor is maintained at 140—180°C and 500—800 kPa (5—8 atm). The heat of reaction is removed by vaporization of water and excess -xylene these are condensed, water is separated, and -xylene is returned continuously (72,74). Cooling coils can also be used (70). 

Metallurgy. The extraction and separation of metals and plating baths have involved quinoline and certain derivatives (see Electroplating Metal SURFACE TREATiffiNTs Exthaction). 

The purity of the cerium-containing materials depends on the appHcation as indicated in Table 3, and purity can mean not only percentage of cerium content but also absence of unwanted components. For some uses, eg, gasoline production catalysts, the lanthanides are often used in the natural-ratio without separation and source Hterature for these appHcations often does not explicitly mention cerium. Conversely, particulady in ferrous metallurgy, cerium is often assumed to be synonymous with rare-earth or lanthanide and these terms are used somewhat interchangeably. 

Packing corroded away (twice). Poor separation. Pieces of packing in pump suction. Wrong metallurgy specification error. 

I Precedence must in fact be given to the South American Indians to whom platinum was available only in the form of fine, hand-separated grains which must have been fabricated by ingenious, if crude, powder metallurgy. 

Because of the magnitude of the task of preparing the material for this new edition in proper detail, it has been necessary to omit several important topics that were covered in the previous edition. Topics such as corrosion and metallurgy, cost estimating, and economics are now left to the more specialized works of several fine authors. The topic of static electricity, however, is treated in the chapter on process safety, and the topic of mechanical drivers, which includes electric motors, is covered in a separate chapter because many specific items of process equipment require some type of electrical or mechanical driver. Even though some topics cannot be covered here, the author hopes that the designer will find design techniques adaptable to 75 percent to 85-1- percent of required applications and problems. 

Metallurgy includes separation, conversion, reduction, and refining steps. The starting material is an impure ore, and the end product is pure metal. 

Sulfate solubility properties are the basis for other industrial uses of sulfuric acid. One example is in the metallurgy of titanium. One of the major ores of titanium is FeTi03, which is treated with sulfuric acid to separate titanium from iron ... 

Extractive metallurgy covers a huge range of mechanical and chemical processes, some of which date back several thousand years.1,2 In terms of recovery from primary sources (metal ores) these processes are often broken down into the unit operations concentration, separation,... 

Sajn, R. 2006. Factor Analysis of Soil and Attic-dust to Separate Mining and Metallurgy Influence, Meza Valley, Slovenia. Mathematical Geology, 38, 735-747. 

He, J.Z., and Liu, M.X., Innovation in Separation Technology for Fine Gravity Semi-Products, Mineral Processing and Extractive Metallurgy, IMM, London, 1984. pp. 553-562. 

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